Intermetallic Aluminide Polycrystalline Diamond Compact (PDC) Cutting Elements

ABSTRACT

Machining and cutting tools including, but not limited to, rotary drill bits, mining tools, milling tools, wood shredders, reamers and wire dies formed with at least one substrate having a layer of polycrystalline diamond disposed thereon. The polycrystalline diamond layer may be generally described as a polycrystalline diamond compact (PDC) or PDC layer. The PDC may be formed by using an intermetallic aluminide catalyst. One example of such catalyst may include nickel aluminide used to form diamond to diamond bonds between adjacent diamond particles.

CROSS REFERENCE TO RELATED APPLICATIONS

This application claims the benefit under 35 U.S.C. §119(e) of U.S.Provisional Application No. 60/883,938, entitled “IntermetallicAluminide Polycrystalline Diamond Compact (PDC) Cutting Elements,” filedJan. 8, 2007.

TECHNICAL FIELD

The present disclosure is related to rotary drill bits and associatedcutting elements and more particularly to fixed cutter drill bits andassociated cutting elements and/or inserts with hard layers of cuttingmaterial disposed on at least one portion of the cutting elements and/orinserts.

BACKGROUND OF THE DISCLOSURE

Polycrystalline Diamond compositions were originally developed byGeneral Electric. An early reference to manufacture of these compositesin an ultra high pressure press is U.S. Pat. No. 3,141,746 to De Lai. Inthis reference De Lai describes a family of metals that may be used toprovide a catalyst for diamond to diamond bonding in the manufacture ofa polycrystalline diamond composite (sometimes referred to as a“polycrystalline diamond compact”) (PDC). The metal catalysts includedby De Lai are iron, cobalt, nickel, ruthenium, rhodium, palladium,osmium, iridium, platinum, titanium, chromium, manganese, and tantalum.General Electric continued to test various metal catalyst combinationsthroughout the 1960's and 1970's as is evident in the literature of PDCdevelopment. Nickel, aluminum, and alloys thereof have been used asbinder catalysts for cubic boron nitride (CBN) compacts and PDC.

In the mid 1980's new intermetallic materials, including nickelaluminide (Ni₃Al) began to find commercial application. Prior to the mid1980's nickel aluminide was often considered as having little commercialvalue due to inherent brittleness and less than desired hardness. Theaddition of approximately 1% boron during production of intermetallicnickel aluminide (INA) made it stronger or harder and more ductile whileat the same time maintaining high heat transfer capability. A key patentin this area is to Huang et al., U.S. Pat. No. 4,478,791.

Recent developments of Intermetallic Bonded Diamond (IBD) by Wittmer andFilip as described in US Patent Application Publication 2006/0280638published on Dec. 14, 2006 and International Publication Number WO2006/107628 published by WIPO on Oct. 12, 2006 disclose the use ofnickel aluminide as a binder material during production of IntermetallicBonded Diamond (IBD). Two further publications “Final Technical ReportMar. 1, 2004 through Dec. 31, 2004” and “Final Technical Report Jan. 1,2005 through Sep. 30, 2005” for the project titled “Intermetallic-BondedDiamond Tools for Coal Mining” further describe their work andobservations.

Wittmer and Filip use various methods to produce IBD compositesincluding: heating in a furnace with continuous flowing argon,vacuum/pressure sintering, and hot isostatic pressing. Hot isostaticpressing is well known in the art and is the process often used to makeimpregnated diamond segments for rotary drill bits and other downholetools. Typically such segments may include a copper/nickel binder tobind a mixture of tungsten carbide powder and small diamond particles.It is important to note that IBD composites developed by Wittmer andFilip do not involve diamond to diamond bonding but rather form metallicbinder with diamond particles disposed therein.

Wittmer and Filip have identified several advantages to their IBDcomposites. These composites appear to be more resistant to thermaldegradation than composites that use copper/nickel alloys or othermetals as a binder. In addition it appears that the use of nickelaluminide may retard the tendency of diamond to graphitize at highertemperatures where diamond graphitization typically occurs withcopper/nickel binders.

SUMMARY OF THE DISCLOSURE

One aspect of the present disclosure may include ultra high pressuremanufacturing of polycrystalline diamond composite (PDC) using anintermetallic aluminide as a catalyst and forming cutting elements orinserts with PDC's resulting from this process. For example, PDC'sformed at least in part by using an intermetallic aluminide as acatalyst may be attached to a substrate to produce PDC cutters forrotary drill bits.

PDC cutters incorporating teachings of the present disclosure maybenefit from high heat transfer capabilities of intermetallic aluminideas compared to prior catalysts such as cobalt used to form PDC's. Highheat transfer may mitigate possible effects of differences betweenrespective coefficients of expansion of intermetallic aluminide anddiamond. Heat transfer capabilities of an intermetallic aluminide mayact synergistically with the diamond crystals of such PDC's to rapidlydissipate heat generated by friction at the cutting tip or cuttingsurface.

PDC cutters incorporating teachings of the present disclosure maybenefit from an intermetallic aluminide's ability to retard diamondgraphitization at higher than typical temperatures and in the presenceof a ferrous work piece. Historically cubic boron nitride cutters havebeen used to machine ferrous materials due to the well knownineffectiveness of diamond in this application. Cubic boron nitride isgenerally not as hard and wear resistant as diamond but is superior todiamond in ferrous machining applications. The capabilities of PDCcutters manufactured using an intermetallic aluminide as a catalyst mayovercome the historic inapplicability of a PDC to satisfactorily machineferrous materials and may offer a superior alternative to cutters madefrom cubic boron nitride.

IBD composites using nickel aluminide may be capable of cutting ferrousmaterial, such as gray cast iron, over long periods of time with verylittle wear of cutting surfaces formed with such IBD composites. It hasalways been a given in machining ferrous materials that diamond reactschemically with ferrous material and breaks down or graphitizes quicklyat a frictional interface between the diamond cutting element and theferrous material. This has been the case with cutting surfaces formedwith natural diamond, synthetic diamond, impregnated diamond and PDC.Apparently IBD composites made with nickel aluminide may not experiencesuch break down of cutting surfaces or graphitization of associateddiamond. Apparently thermal and/or chemical processes that break downdiamond during ferrous cutting applications may be significantlyretarded by using nickel aluminide as a binder material to form a PDC.

BRIEF DESCRIPTION OF THE DRAWINGS

A more complete and thorough understanding of the present embodimentsand advantages thereof may be acquired by referring to the followingdescription taken in conjunction with the accompanying drawings, inwhich like reference numbers indicate like features, and wherein:

FIG. 1 is a schematic drawing showing one example of an aluminide PDCcutting element or cutter incorporating teachings of the presentdisclosure;

FIG. 2 is a schematic drawing in section showing another example of analuminide PDC cutting element or cutter incorporating teachings of thepresent disclosure; and

FIG. 3 is a schematic drawing in section with portions broken awayshowing a layer of hard cutting material formed from diamond pelletsusing an intermetallic aluminide catalyst.

DETAILED DESCRIPTION OF THE DISCLOSURE

Preferred embodiments of the present disclosure and various advantagesmay be understood by referring to FIGS. 1, 2 and 3 of the drawings. Likenumerals may be used for like and corresponding parts in the variousdrawings.

The terms “rotary drill bit” and “rotary drill bits” may be used in thisapplication to include various types of roller cone drill bits, rotarycone drill bits, fixed cutter drill bits, drag bits, matrix drill bitsand PDC drill bits operable to form a wellbore extending through one ormore downhole formations. Rotary drill bits and associated componentsformed in accordance with teachings of the present disclosure may havemany different designs and configurations. Cutting elements and bladesincorporating features of the present disclosure may also be used withreamers, near bit reamers, and other downhole tools associated withforming a wellbore.

The terms “cutting element” and “cutting elements” may be used in thisapplication to include various types of compacts, cutters and/or insertssatisfactory for use with a wide variety of rotary drill bits. The term“cutter” may include, but is not limited to, face cutters, gage cutters,inner cutters, shoulder cutters, active gage cutters and passive gagecutters.

Polycrystalline diamond compacts (PDC), PDC cutters and PDC inserts areoften used as cutting elements for rotary drill bits. Polycrystallinediamond compacts may also be referred to as PDC compacts.

For some applications cutting elements formed in accordance withteachings of the present disclosure may include one or morepolycrystalline diamond layers formed on a substrate by using anintermetallic aluminide catalyst. Such layers may sometimes be referredto as “cutting layers” or “tables”. Cutting layers may be formed with awide variety of configurations, shapes and dimensions in accordance withteachings of the present disclosure. Examples of such configurations andshapes may include, but are not limited to, “cutting surfaces”, “cuttingedges”, “cutting faces” and “cutting sides”.

The terms “cutting structure” and “cutting structures” may be used inthis application to include various combinations and arrangements ofcutting elements, cutters, face cutters, gage cutters, impact arrestors,protectors, blades and/or other portions of rotary drill bits, coringbits, reamers and other downhole tools used to form a wellbore. Somefixed cutter drill bits may include one or more blades extending from anassociated bit body. Cutting elements are often arranged in rows onexterior portions of a blade or other exterior portions of a bit bodyassociated with fixed cutter drill bits. Various configurations ofblades and cutters may be used to form cutting structures for a fixedcutter drill bit in accordance with teachings of the present disclosure.

One embodiment of the present disclosure may include using nickelaluminide as a catalyst during production of PDC cutters. Nickelaluminide is not a typical alloy of nickel and aluminum, rather nickelaluminide is a well ordered crystalline compound expressed as Ni₃Al. Itis one of an emerging materials family of intermetallic aluminides thatalso includes iron aluminide, cobalt aluminide, titanium aluminide,nickel-platinum aluminide, nickel-titanium aluminide, niobium aluminide,ruthenium aluminide, scandium aluminide, and zirconium aluminide. Theprocess may involve loading a cell with a WC substrate inclusive of asmall percent (2% to 15%) of cobalt and covering one end or one portionof the substrate with a mixture of intermetallic nickel aluminide powderand diamond particles of a size range between approximately 3 microns to60 microns. A size range of 5 microns and 25 microns of diamondparticles may be preferred for some applications.

Resulting PDC's may have a diamond volume percent between approximately50% and 95% of the total volume of each PDC. A diamond volume percentbetween approximately 75% and 92% may be preferred for someapplications. A substrate with a mixture of diamond particles and anintermetallic aluminide may be placed in a conventional containerassociated with manufacture of PDC cutters. The loaded cell may then beplaced into an ultra high pressure press and brought up to pressures andtemperatures for time periods as are well known in the art and describedat length in the literature. The result may be a PDC cutter bettersuited to high temperature applications and/or to ferrous machiningapplications than prior art PDC cutters.

FIG. 1 shows a cutting element which includes a substrate with a PDClayer disposed on one end thereof. The PDC layer may be found using anintermetallic aluminide catalyst as previously described.

For some applications a wafer of intermetallic nickel aluminide may beplaced between one end of a substrate and powder mixture ofintermetallic nickel aluminide and diamond particles. This wafer may actas a barrier to large scale migration of cobalt from the substrate intothe PDC during the pressing cycle. If too much cobalt enters into thePDC during the process then advantages obtained through the use of anintermetallic aluminide catalyst may be reduced.

FIG. 2 shows a cutting element which includes a layer or wafer ofintermetallic aluminide disposed between one end of a substrate and anassociate PDC layer. The PDC layer may be formed using an intermetallicaluminide as previously described. The substrates shown in FIGS. 1 and 2may be formed from a wide variety of materials including, but notlimited to, tungsten carbide (WC).

PDC cutters made using the teachings of the present disclosure areespecially applicable to rock drilling tools, down hole drilling andreaming tools, mining tools, ferrous and non-ferrous machining tools,wire dies, wood processing, and diamond saw blades for rock quarrying.

Although the present disclosure and its advantages have been describedin detail, it should be understood that various changes, substitutionsand alternations can be made herein without departing from the spiritand scope of the disclosure as defined by the following claims.

1. A cutting element comprising: a substrate having at least one layerof a polycrystalline diamond compact disposed thereon; and thepolycrystalline diamond compact formed in part by using an intermetallicaluminide as a catalyst to form diamond to diamond bonds betweenadjacent diamond particles.
 2. The cutting element of claim 1 whereinthe intermetallic aluminide further comprises nickel aluminide.
 3. Thecutting element of claim 1 further comprising the intermetallicaluminide selected from the group consisting of iron aluminide, cobaltaluminide, titanium aluminide, nickel-platinum aluminide,nickel-titanium aluminide, niobium aluminide, ruthenium aluminide,scandium aluminide, and zirconium aluminide.
 4. The cutting element ofclaim 1 further comprising an insert for a fixed cutter rotary drillbit.
 5. The cutting element of claim 1 further comprising a portion of adownhole tool selected from the group consisting of a rotary drill bit,reamer, near bit reamer, hole opener and coring bit.
 6. The cuttingelement of claim 1 further comprising at least one portion of a toolselected from the group consisting of a mining tool, a machining toolused to cut ferrous materials, a machining tool used to cut non-ferrousmaterials, a machining tool used to process wood and other fibrousmaterials and a saw blade used to cut rocks such as limestone andgranite, concrete, cermets and other hard materials.
 7. The cuttingelement of claim 1 further comprising: the substrate having a first end;and the at least one layer of the polycrystalline diamond compactdisposed on the first end of the substrate.
 8. The cutting element ofclaim 7 further comprising a layer of intermetallic aluminide disposedbetween the first end of the substrate and the at least one layer of thepolycrystalline diamond compact.
 9. The cutting element of claim 7further comprising the intermetallic aluminide used to form the layer ofpolycrystalline diamond compact selected from the group consisting ofiron aluminide, cobalt aluminide, titanium aluminide, nickel-platinumaluminide, nickel-titanium aluminide, niobium aluminide, rutheniumaluminide, scandium aluminide, and zirconium aluminide.
 10. The cuttingelement of claim 7 further comprising: a plurality of void spaces formedbetween adjacent diamond particles bonded with each other by diamond todiamond bonds; and the intermetallic aluminide disposed within the voidspaces formed between adjacent diamond particles.
 11. A rotary drill bitoperable to form a wellbore in a downhole formation comprising: a bitbody having one end operable for connection to a drill string; aplurality of cutting elements disposed on exterior portions of the bitbody; the cutting elements defined in part by a respective substrate anda respective layer of hard cutting material disposed on one end of therespective substrate; and the layer of hard cutting material including apolycrystalline diamond compact formed at least in part by using anintermetallic aluminide catalyst.
 12. The drill bit of claim 11 furthercomprising at least one of the substrates having a generally circularcross section.
 13. The drill bit of claim 11 further comprising at leastone of the substrates having a generally noncircular cross section. 14.The drill bit of claim 11 further comprising: a bit face profile havingan inverted cone shaped configuration opposite from the one end of thebit body; an opening formed in the bit body proximate the inverted coneshaped portion of the bit face profile; a substrate having a layer of apolycrystalline diamond compact formed in part by intermetallicaluminide catalyst; a post extending from the substrate; and the postdisposed in the opening in the bit body with the layer of thepolycrystalline compact operable to engage formation materials adjacentto the inverted cone shaped portion of the bit face profile.
 15. Thecutting element of claim 11 wherein the intermetallic aluminide furthercomprises nickel aluminide.
 16. The drill bit of claim 11 furthercomprising the intermetallic aluminide selected from the groupconsisting of iron aluminide, cobalt aluminide, titanium aluminide,nickel-platinum aluminide, nickel-titanium aluminide, niobium aluminide,ruthenium aluminide, scandium aluminide, and zirconium aluminide.